Producing residual oil products



Patented Jan. 11, 1927.

UNITED. STATES PATENT OFFICE.

EDWARD E. BABTELS, OF W HITING, INDIANA, ASSIGNOR TO STANDARD OIL COM-PANY, OF WHITING, INDIANA, A CORPORATION OF INDIANA.

PRODUCING RESIDUAL 'OIL PRODUCTS.

No Drawing.

The, present invention relates to improvements in the handling ofpressure tar, by which term is designated the residual product of theconversion under pressure ot hydrocarbon'oils into gasoline, the lighterpor-- tions thereof (containing gasoline) having been removed. Anaverage pressure tar, resulting from the operation of the Burtonprocess, for example, may have a Baume gravity of 18.

In the running down of pressure tar for the formation of various gradesof road oils and fluxing oils, it has hitherto been customary to employseries of stills in ordinary continuous operation, the operation of theentire battery or series of stillsbeing controlled for the production,as a residue, of a specific one of the commercial grades of such oils.Thus it hasbeen customary to produce from pressure tar in this mannerfour or more products of increasing vis'osity, some being designated asroad oils and the heaviest as fluxing oils. The lightest of theseproducts, the first road oil, may have, for example, a viscosity of 1.5Engler. The heaviest or' fluxing oil product may have a viscosity of 6Engler, intermediate road oil products having viscosities, for example,of 2 5 Engler and 3 Engler, the viscosity being measured in each case at212 F.

Variation in the simultaneous market requirements for the variousproducts has made this method of running very uneconomical anddisadvantageous, usually it has been found necessary to make certain ofthe products in batch stills While the battery is in use for themanufacture of the products for which there is the greatest demand.

In carrying out the present'invention, a battery or series of successivestills is used in running down the pressure tar; an intermediateresidual product is drawn off from an intermediate still in the system,th scorresponding to the lightest of the desired commercial products,and a residue or tar is simultaneously drawn off from'theend of thesystem, this corresponding to the heaviest of the commercial products.ample, if a system consisting "of ten stills is operated continuously onpressure tar of For ex Application filed November 17, 1924. Serial No.750,489.

the character above set. forth, the light road oil (viscosity 1.5Engler) may be drawn off as a residue, for example, from the seventhstill. and the fluxing oil (viscosity 6 Engler) may suitably be drawnoff as a residue from the last still. The jintermediateproducts ot' thedesired viscosities may then be produced in the desired quantities inaccordance with market demands by mixing or blending the heavy residueand the intermediate product drawn oil. Thus, by mixing them in theproportion of about 45 to 55, the second grade of road oil abovereferred to (viscosity 2.5 Engler) may be produced and by mixing them inthe proportion of about 70 to 30, the heaviest road oil (viscosity 3Engler) may be produced.

It is to be understood that the figures and proportions above given areintended for purposes of illustration only, and that the process mayreadily be adapted for use in connection with any type ofresidual'products' produced by continuous distillation, either with firealone or with lire and steam.

I claim:

1. The method offorming a plurality of residual products by continuousdistillation of a hydrocarbon oil in a succession of stills, whichcomprises drawing off as a residual from an intermediate one of saidstills the desired product of the lightest grade, drawing off from theend still. a residue having the properties of the desired product of theheaviest grade, and blending said products to produce the desiredproducts of intermediate grade.

2. The method of reducing pressure tar for the formation of a pluralityof residual products of predetermined viscosities coin.-

at 212 F., and blending said residues to produce intermediate products(ii-desired visrosities- EDWARD E. BARTEL'S.

